Pin carriage to clutch interlock mechanism in a ten-key adding and subtracting machine



July 13, 1965 G. E. BULLOCK PIN CARRIAGE TO CLUTCH INTERLOCK MECHANISMIN A TEN-KEY ADDING AND SUBTRACTING MACHINE Filed Sept. 12, 1962 3Sheets-Sheet 1 INVENTOR. 6,256.5 gflulfock 3,194,496 IN A July 13, i965s. E. BULLOCK PIN CARRIAGE TO CLUTCH INTERLOCK MECHANISM TEN-KEY ADDINGAND SUBTRAC'I'ING MACHINE Filed Sept. 12, 1962 3 Sheets-Sheei'. 2

g, JNVENTUR. $1 6 .31 [Zack Attorn ys July 13, 1965 G. E. BULLOCK PINCARRIAGE TO CLUTCH INTERLOCK MECHANISM IN A TEN-KEY ADDING ANDSUB'IRAGTING MACHINE Filed Sept. 12, 1962 3 Sheets-Sheet 3 3 mm m bAttom y United States Patent s 194 496 PIN CARRIAGE T0 cLUTcu INTERLOCKMECHA- NISM IN A TEN-KEY ADDING AND SUBTRACT- ING MACHINE Giles E.Bullock, 7960 Corbin Ave., Reseda, Calif. Filed Sept. 12, 1962, Ser. N223,112 .5 Claims. (Cl. 235-130) This invention relates to mechanicalcomputing machines of the type utilized for example in accounting work,in adding, subtracting, multiplying and dividing, and wherein a pincarriage having a series of digit position banks of memory pins (with,for example, nine pins in each bank and nine banks) is responsive tomanual actuation transmitted from the keys of a ten-key keyboard in akey-punching operation. In such operation, the punched keys correspondto the digits of a number to be registered in the machine for additionto (or subtraction from) a series of previously registered numbers. Thekeys, as they are punched, are operative progressively on the successivebanks of memory pins, the pin carriage being advanced in a steppingaction to successive digit positions so as to bring .a new bank ofmemory pins into operative relation to the manual actuator keysfollowing each actuation of a key on the keyboard. In such a machine,when a selected number is thus registered on the pin carriage(functioning as a memory device) an add or subtract key is pressed toinitiate a power cycle wherein the dial wheels of a conventional dialwheel assembly are rotated and stopped by projecting pins in the pincarriage, in positions registering the number that was impressed on thepin carriage, While the invention is applicable to a manually poweredmachine wherein this power cycle is carried out by manually oscillatingan actuator lever, the invention has its primary usefulness as appliedto an electric motor driven calculator wherein the depression of the addor subtract key initiates a cycle of operation of a motor which drivesthe dial wheels, and at the same time effects a printing operationwherein the platen which supports the record tape is moved forwardly topress the tape against type elements carried on the peripheries of thedial wheels.

The machine to which the invention is applied, further embodies acorrection (clearing) key which can be actuated to clear an erroneousnumber from the pin carriage.

This is done by restoring the pin carriage to its home position, and thecorrection key is directly linked to an automatic clearing mechanismwhich is power-operated at the end of each power cycle. In such amachine, it is possible to jam the mechanism if any of the power cyclekey-stadd, subtract, non-add, sub-total and total keys) is actuatedsimultaneously with actuation of the correction key, since the pincarriage must be in a stationary position during each power cycle, andif it is moving in response to actuation of the correction key when apower cycle is initiated, the power-driven parts will inevitably jamagainst the displaced pin carriage parts.

The principal object of this invention is to provide an interlockbetween the pin carriage clearing linkage and the power cycle keys suchthat the actuation of any power cycle key will block the movement of theclearing linkage and, vice 'versa, the actuation of the correction keywill result in blocking the actuation of the power cycle keys.

The invention is especially directed to the improvement of anexceedingly compact, light-weight machine which has appeared on themarket in recent years but has met with only slight success because oflack of protection against the jamming referred to above. Furthermore,this machine is so compact'that it involves a very distinct problem ofspace for accommodating an interlock mechanism. Accordingly, a furtherand specific object of the invention is to provide an interlockmechanism which 3,194,496 Patented July 13, 1965 occupies a shallowspace at the very forward extremity of the machine, between the case andthe frame. The interlock is linked to the clearing linkage at one sideof the machine and to the power control linkage at the opposite side ofthe machine in a simple, compact and easily serviced arrangement.

Other objects and advantages will become apparent in the ensuingspecification and appended drawings in which:

FIG. 1 is a plan view of an interlock mechanism embodying the invention,including both portions of the machine on which the interlock mechanismis operative but omitting the majority of the conventional operatingmechanism of the machine;

FIG. 2 is a right side elevational View of the same;

FIG. 3 is a front elevational view of the same;

FIG. 4 is a left side elevational view of the same.

General description Referring now to the drawings in detail, theinvention is illustrated therein as embodied in a calculating machinewherein power cycles are initiated by a series of power keys in a groupindicated at A, operating on clutch actuating linkage B to release aclutch-cam unit C for rotation transmitted to it from power mechanism Dwhich is energized simultaneously by the clutch actuating linkage B.

Clutch-cam unit C, which is thus rotated one revolution, is operativelyconnected to a series of actuator rack units E in a manner to releasethem for spring-biased upward movement. The upward movement of some ofthe rack units B will be arrested by projected memory pins of a pincarriage F, in accordance with a number registered on the pin carriageby previous keyboard actuation. None of the keyboard mechanism isillustrated except the group of ten numeral keys indicated at K, but itwill be understood that it is operative to set the pins of successivebanks in the carriage F in response to depression of successive numeralkeys, and that the actuated pins will be projected into the path ofupward movement of respective rack units E. Thus, in the operation of apower cycle, one or more of the rack units E will be arrested inpositions registering the number that was previously impressed on thepin carriage F.

The upward movement of the respective rack units E is transmitted byrack and pinion action to respective dial wheels of a dial unit G.

The dial wheels are fixed to respective pinions which are constantly inmesh with the racks of their respective rack units E, so that theactuated dial wheels will be set to the correct positions correspondingto the keys that have been punched, as determined by the positions ofelevation of the respective rack units, without possibility of ernor. Itmay be noted at this point that each of the rack units carries on it anaccumulator actuator unit having two-Way-operating racks selectivelybrought into operating position depending on whether the add or thesubtract button is depressed, whereby the numbers registered on the dialassembly are transferred by the accumulator mechanism into a sub-totalor total. However, the present invention affects the accumulatormechanism only indirectly through the respective rack units, andaccordingly, no part of the accumulator mechanism is disclosed herein.

It should also be pointed out that much of the conventional mechanism ofthe'machine to which the invention is applied, if disclosed at allherein, is shown schematically and not in full mechanical detail, so asto avoid unnecessary obscuring of the improvements constituting theinvention, the primary purpose of the disclosure being to identify thetype of machine to which the invention is applied.

Each of the dial wheels of dial assembly G has a series of peripheraltype units, including the ten digits of the decimal system plus othersymbols which may be desirable for indicating various conditions ofoperation. The machine further includes a platen unit H having suitablesupport arms or carriage mechanism for advancing the platen roll (andthe tape I supported thereby), into impression contact with the typewhich are positioned by the indexing of the dial wheels, for imprintingthe number that has been registered on the machine by keyboardactuation.

With the conventional calculator mechanism brieiiy outlined above, theinvention combines an interlock mechanism which is indicated generallyat J and which extends across the front end of the machine as bestillustrated in FIG. 1.

In the keyboard actuating mechanism, indicated at K in FIG. 1, a zerobar and nine numeral keys are designated by their respective numerals 9,ll, 2, 3, 4, 5, d, 7, 8 and 9 respectively; add, subtract, non-add,sub-total and total keys of group A being indicated by the plus andminus signs and by the letters N, S and T respectively. A multiplicationbutton (which has the conventional function of preventing the clearingof the machine so that successive adding operations can be performedwithout losing the preset number from the memory mechanism) is indicatedby the letter X. These are indicating characters actually imprinted onthese respective keys. The respective numeral keys K are connected tosuitable linkage (not shown) which is disposed in the area seen to theleft of the pin carriage F in FIG. 2, so that upon manual actuation of akey, a respective memory pin of carriage P will be shifted intoprojecting relation to the path of movement of a respective rack unit E(thus remembering the numerals punched on the keyboard).

It may now be noted in FIG. 1 that the numeral keys tl9 are arranged ina compact group opposite the center of the area in which the pincarriage F is arranged to slide, so that the respective actuatinglinkages may be directly associated with the pins of carriage F. Also,it should be pointed out that the keys of group A including the add,subtract, multiply, non-add, sub-total and total keys, referred above,constitute the keys of the power cycle group, the operation of which isto be protected by the interlock mechanism of this invention.

The conventional mechanism further includes a correction key Q which isin the form of a lever. A clearing linkage R is alternatively operablemanually by the correction key Q and by power operation during eachpower cycle. Its function, in general, is to restore the pin carriage Fto a starting or home position after having been successively shifted tosucceeding digital positions by escapement mechanism operated by therespective numeral keys of group K, whereby the pin carriage is advancedone digital position each time a numeral key is touched.

Detailed description Amplifying the foregoing generalized outlinedescription, I will now describe the illustrated portions of the machinemore in detail.

In group A of power actuator keys, each key embodies a button 19, a keybar 11, a cam pin 12 carried by bar 11, and suitable supporting guides(not shown) Connected to the lower ends of the respective key bars 11are respective elements of linkage (not Shown) including bell cranklevers and push bars extending rearwardly from keys S and T, and rockerlevers extending rearwardly from other keys of the A group for effectingvarious control actions on the clutch-cam unit C and other parts of thepower mechanism; whereby the actuation of the various keys of group Awill initiate various power cycles such as adding, subtracting,sub-totaling and totaling, etc., there being some type of-poweractuation in each instance. The interlock mechanism J of the inventionblocks the transmission of movement through these various linkageswhenever the clearing mechanism R is away from its home position as aresult of movement of correction lever Q. It will be understood that theclearing mechanism R will not be power operated at the wrong time, sincethe machine is designed to effect the clearing operation at the end of apower cycle and not during the power cycle.

Clutch actuation linkage B constitutes a specific part of the linkagejust referred to. It comprises a clutch actuating slide bar .15 having aseries of cam notches 16 in inclined positions in its upper side andcoperating with the cam pins 12; of the respective keys of group A forreleasing the clutch as a preliminary step in each power cycle. Theslide 15 is connected by a trip link 17 to a holding latch 18 having ajaw 19 normally en aged with a tooth 29 on the periphery of acooperating holding disc 21. Latch 18 is in the form of a lever pivotedat 22 to the frame, and having a tail portion 23 engaged beneath the endof a switch actuator rocker arm 24.

Power mechanism D includes the arm 24 which is pivoted at 25 to theframe and has an actuator finger 26 for depressing a spring finger 27 ofa microswitch 2.3 which closes the circuit to an electric motor 29.Motor 29 has a driven pinion 30 which drives an idler gear 31 carrying apinion 32 which in turn drives a gear 33 on the shaft of clutch-camassembly C.

Clutch-cam assembly C includes the latching parts 20- 22 previouslydescribed; a cam shaft 3 on which the gear 33 is mounted; a clutchmechanism (not shown) for clutching the gear 33 to the shaft 34 when oneof the keys of the power cycle group A is depressed; and a series ofcams, secured to the shaft 34-, one of said cams being disclosed at 35.The cam 35 operates against the follower end of a rocker arm 36,fulcrumed on a pivot 37 and, at its opposite end, supports one end of ahold down bar 38 extending across the accumulator section of themachine. The cam 35 and rocker arm 36 are duplicated at both sides ofthe accumulator section, whereby the bar 38 will be bodily raised andlowered by swinging movements of the two rocker arms 36. In its loweredposition shown in FIG. 2, the bar 38 holds down all of the rack units Ein their home positions. As the cam shaft 34 is released for onerevolution, the earns 35 will rotate away from the follower ends ofrocker arms 36, releasing them so that the rack units E are free to moveupwardly in response to spring loading, until stopped by projecting pins57 of pin carriage F. It will be understood that the clutch-cam assemblyC includes other elements not necessary to this description andaccordingly not shown herein.

Rack assembly E comprises a plurality of rack units each embodying avertically slidable arm 41 having longitudinal slots 42 through whichare extended guide bars 43; having at their upper ends rack teeth 44 forreceiving resetting movements; and having at their lower ends, stopringers d5 projecting beneath the hold down bar 38, and into positionsfor engagement with projected memory pins of unit F. Spring power forelevating the units E is provided by respective coil springs 46, eachconnected under tension to a respective stop finger 45 at its lower endand to a frame anchor 47 at its upper end.

It may now be noted that the hold down bar 38 extends above the stopfingers 45 so as to hold all of the rack units E in their lowered homepositions until released for upward movement in the beginning of a powercycle.

Pin carriage F comprises a carriage frame Stl mounted for transversesliding movement on vertically-spaced slide bars 51, 52, the ends ofwhich are mounted in the machine frame 58 as shown in FIG. 1. Thecarriage F is advanced by a coil spring 54 which is connected undertension between the frame 53 and a tab 55 on carriage frame 50. Thecarriage F is held back by escapement mechanism (not shown) suchescapement mechanism being successively actuated by the numeral keys ofgroup K so as to advance the carraige one digital position for eachactuation of a key. Such escapement mechanism is well known not only inthe adding machine art but also in the typewriter art and accordingly isnot herein illustrated.

clearing mechanism R hereinafter described.

In the carriage frame 50 are mounted a series of vertical banks ofmemory pins 57, each having nine pins in vertically spaced relation andthere being nine banks in horizontally spaced relation. As the carriageis advanced to successive digital positions, successive banks of pinsare brought into registration with the actuator linkage of the numeralkey group K., Such actuator linkage is effective to displace a pin(corresponding to a punched key) rearwardly (rightwardly asseen in FIG.2) to a position over-hanging the tip of a respective stop finger 45 ofa rack unit E. As a key is punched and a pin is projected, theescapement mechanism will be actuated to release the carriage F foradvancement to the next digital position and the next punched key willsimilarly project driven by the rack teeth 41 of a respective rack unitE.

Thus the dial wheel 60 is positioned in a numeraLindicating positiondetermined by the position at which the rack unit E has been arrested inits upward movement. Each dial vwheel 60 includes appropriate type forimprinting on the tape I a numeral correspondingto the position to whichit has been set.

Ploten unit H comprises a conventional platen roll 65 carried byrespective arms 66 which in turn are controlled by a cam (not shown) oncam shaft 34 in a manner analogous to the rocker arms 36 of the holddown mechanisrn. Each revolution of the cam shaft accordingly advancesthe platen roll 65 to bring the tape Iinto engagement with the type ofdial wheels 60 in accordance with the positioning thereof by the unitsE.

Correction key Q, which includes parts directly involved in the presentinvention, comprises a lever 70 disposed in a vertical plane immediatelyadjacent the leftward rail of frame 58 on the outer side thereof andpivoted thereto by a fulcrum pivot 71; a lever arm 72 projectingdownwardly from pivot 71 and connected to the clearing linkage R; and anintegral blocking finger 73 projecting forwardly from the fulcrum pivot71. On its forward end, finger 73 hasan arcuate blocking face 74,concentric with pivot 71. Finger 7'3 constitutes a portion of theinterlock mechanism J. The lever 70 has a retracted home position, shownin full lines in FIG. 4 wherein the finger 73 projects above the planeof a cooperating part of blocking mechanism I, so thatit can prevent themovement of the lever 70 forwardly into an operating range so long asthe mechanism J is in blocking position beneath the finger 73.

Correctionkey Q, reset mechanism R, and their associated parts are shownin direct view in FIG. 4, looking at the left side of the machine wherethese parts are located. However, they are also seen in phantom in FIG.

-2, illustrating their positional relationship (lengthwise of themachine), to the other components.

Clearing mechanism R comprises a slide 75 having in its respective endportions, longitudinal slots 76 by which it is slidably mounted on studs77 projecting from the frame. Slide 75 is mounted in direct slidingengagement with the outer face of frame 58 as best shown in FIG. 1,

and has a yoke 78 formed as an integral extension from the upper marginthereof and projecting inwardly through a slot 79 in the frame 58. Yoke78 has a transverse slot 80 therein. l

A bell crank lever 81, disposed in a horizontalplane near the bottom ofthe machine, is fulcrumed to the frame on a vertical pivot 82. Lever81has a relatively short lever arm 83 extending beneath yoke 78 andprovided with an upwardly projecting roller 84 which is engaged in slot7 80; and has a relatively long arm 85 projecting diagonally inwardlyand rearwardly toward the center of the machine and connected by a draglink 86 to the pin carriage F, one end of the link 86 being pivoted tothe end of lever arm 85 audits other end being pivotally connected to anear 87 projecting forwardly from the pin carriage frame 50. The linkage78-87 is arranged to transmit shifting movements in both directionsbetween the pin carriage F and the slide 75 of clearing linkage R, instages of successive digital positions of the pin carriage.

An abutment pin 88 is secured in slide 75 and projects outwardly acrossthe path of horizontal swinging movement ofthe lower end of thecorrection lever arm 72. In the home positions of the lever 70 and slide75, the abutment pin 88 is spaced rearwardly rfom the lever arm 72 asbest indicated in FIG. 4. The spacing is such that the slide '75 mayshift from its home position to a fully shifted position correspondingto the limit position of stepping movement of pin carriage F, beforecontact is established with abutment pin 88. During the steppingmovements of pm carriage F, slide 75 will be correspondinglyintermittently advanced from its position shown in full lines in FIG; 4toward the right as seen in that figure, until, in a limit position ofsuch intermittent advancing movements, abutment. pin 88 will rest incontact with or immediately adjacent the lower end of correction leverarm 72. From this position or any intermediate position, the slide 75can be shifted back to its home position by moving the correction lever7t) forwardly, causing its arm 72 to swing rearwardly intocontact withabutment 92 acts against one arm of a bell crank lever 95 pivoted pin88and pushing the slide back to its home position in a continuousmovement. Thus it is possible to restore the pin carriage F to its homeposition prior to effecting a power cycle of operation and to thus avoidhaving the information stored on the pin carriage F transferred'to thedial wheel and printing assembly G and H;

Secured to a suitable transverse frame element in the center of themachine, just rearwardly of the pin carriage slide frame 50, is apin-reset plate 90 having a ramp portion 91 at its forward end (the endwhich is first engaged by theprojected memory pins of carriage F duringa clearing operation). The movement of the projected pins against theramp 91 andalong the body of reset plate 99 effectively returns the pinsto their home positions shown at the left-ward side of carriage 50 inFIG. 2.

In the normal operation of the machine, during a power cycle, movementis transmitted to the slide 75 to draw it rearwardly, thus resetting itto its home position. Such movement is generated by a cam 92 on the camshaft 34. The linkage for transmitting this resetting movement includespull-link 93 which is pivotally linked to a stud 94 projecting outwardlyfrom the rear end of slide 75. Cam

toframe 53 at 96, the other arm of lever 95 having at its end aprojecting pin 97 engageable with a shoulder 98 on pull-link 93 at atime when the link 93 is elevated by operation of a control crank 198(responsive to another cam on shaft 34) the projecting end of link 93being slidably coupled to a laterally projecting guide tab 99 on the endof a vertically-movable arm of crank 198. During each power cycle, theclearing mechanism R will be automatically actuated to return the slide75 to its home position restoring the pin carriage F to its homeposition, with the pins 57 being automatically reset by brushingengagement with reset plate 90. Since the present invention is concernedonly with protecting against the untimely operation of correction key Qor a key of power group A and since the automatic clearing operationjust described is connecting the cam shaft 34 to the slide 75, which issomewhat complex, are only partially disclosed herein.

Interlock mechanism J comprises a rocker lever tilt disposed in a planeparallel to and somewhat below the inclined plane of the keyboard andmounted directly to the underside of a lower keyboard plate tilt (FIG.3) by a pivot Hi2 disposed approximately midway between its ends. Lowerkeyboard plate fill may be a sheet metal stamping, with end tabs 103bent downwardly and secured to the respective side members of frame 53.

Viewing the lever 16% from the forward end of the machine (FIG. 3) ithas at its leftward end a downwardly offset finger 1% which projectsthrough a slot 165 in the leftward member of frame 53. Finger 1% isdisposed in non-blocking relation to the blocking finger 73 ofcorrection lever '74 (clearing the tip of the same) when the lever 160is in its home position shown in full lines in FIG. 1.

At its other end, lever 1% has a tip 1th: which projects through a slot187 in the forward end of clutch actuating slide 315 (in an integralfinger 1&8 projecting downwardly from the forward end thereof). Levertip res is embraced fairly closely between the forward and rearwardextremities of slot 107, with just sufficient clearance to permitfreedom of tilting movement of the tip 1% in the slot. Thus there isprovided a two-way driving connection between the lever tip 166 andslide 15 whereby movement may be transmitted from either of these partsto the other.

At this point it should be noted that the clutch actuating slide 15functions as a common transmitting link for each of the five power keysof group A (the minus key and the keys N, S and T having directconnections between respective actuator pins 12 and slots 16, and theadd key having a more indirect connection through a bell crank, notshown, and a connecting link 110 to the finger 108). Accordingly, thesingle interlock lever 160 provides a blocking connection between eachof these power keys and the correction key Q.

Operation The detailed phases of operation of the various components ofthe machine have been largely described in the foregoing description ofthese units, and at this point I will only review the overall operationof the machine, particularly with reference to the interlock mechanism.

In the novel operation of this machine, the numeral keys of group K willbe selectively operated to register numbers on the pin carriage F bypushing back a pin in each of a number of successive banks of pins, inaccordance with the numeral keys that are depressed and the order inwhich they are depressed, the carriage F shifting sequentially towardthe center of the machine in response to operation of the escapementmechanism, until the selected number is registered. During thekey-punching stage of operation, each advancing movement of pin carriageF away from its home position will be transmitted through linkage 37-73to the slide 75, shifting it successively toward the forward end of themachine. If a nine digit number is punched on the keyboard, the abutmentpin 38 of slide '75 will move to its forward limit position immediatelyadjacent the lower end of correction lever arm '72 (as the result of thenine successive movements resulting from the punching of nine keys).When the key-punching operation is completed, one of the power keys ofgroup A (e.g., the add key) will be depressed, starting the motor 29,releasing the holding mechanism of assembly C, engaging the clutch ofassembly C and effecting one revolution of cam shaft 34. In thisrevolution, the cam mechanism will raise the hold down bar 38 from itsrestraining home position, thus permitting the respective rack units Eto be raised by the respective biasing springs 46, to positionsestablished by engagement of their respective stop fingers 45 with theprojected memory pins of carriage F. The upward movements of rack unitsE will index the dial wheels of assembly G to positions corresponding tothe number punched on the keyboard, and in the terminal phase of thecycle the platen H will be advanced, imprinting this number on the tapeA by contact with the type on the peripheries of dial wheels 60.Finally, the clearing mechanism R will be actuated by connecting link 92to draw the slide 75 rearwardly, thus transmitting movement throughlinkage 78-87 to return the pin carriage F to its home position, theprojected pins 5?? brushing against the reset plate Qt) to erase thenumber that has been registered on the carriage F. At the end of thepower cycle, movement transmitted from the cam shaft 34 through link 92will restore the slide 75 to its home position as previously described,and this movement will be transmitted through linkage '7387 to the slideF, restoring it likewise to its home position. If during the punching ofthe numeral keys, the operator discovers he has made an error, he canmanually restore the carriage F to its home position by pulling thecorrection lever '76 forwardly, bringing the lever arm 72 rearwardlyinto engagement with abutment pin 88 and correspondingly shifting theslide 75 rearwardly, the lever 70, in its forward limit position shownin dotted lines in FIG. 4, completing the return of the slide 75 to itshome position.

If, during such a correction operation, the operator should accidentallystrike one of the keys of the power group A, a power cycle would beinitiated during the clearing movement of memory pin carriage F, and theresulting uncontrolled interference between the power operated parts andthe rearwardly projecting pins would result in damage to theseconflicting parts. The damage can proceed to the extent of breaking offthe projecting pins 57, bending the rack units E into permanentlydistorted positions, and rendering the accumulator mechanisminoperative.

The invention protects the machine against such an occurrence asfollows: as long as all of the power buttons of group A are in theirelevated home positions, the clutch actuating slide 15 will remain inits home position shown in FIG. 2, and the interlock lever tilt) willaccordingly be disposed in its home position with its rightward tip 106in its rearward limit position, and with its blocking finger 104 in itsforward limit position, all as shown in full lines in FIG. 1. In thatposition, the blocking finger 104 will be in non-blocking relation tothe finger 73 of correction lever 76. Consequently, it is possible topull the lever 70 rearwardly to effect the correction operation, thefinger '73 swinging downwar ly and clearing the blocking tip 194 of theinterlock lever.

On the other hand, if one of the power keys of group A is depressed, theclutch actuating slide 15 will be shifted forwardly, and the linkingconnection between its forward finger 1% and the interlock lever tip 196will swing the lever ltitl in the clockwise direction as viewed in FIG.1,

0 to the blocking position shown in broken lines in that figure. Thiswill bring the blocking tip 194 to a blocking position beneath thefinger 73 of correction lever 76) prc venting the rearward swingingmovement of that lever toward its resetting position shown in brokenlines.

Conversely, if the lever 79 has previously been actuated toward itsclearing position, swinging the blocking finger 73 downwardly, thearcuate end face 74 of the finger will be moved into blockinr relationto the rear edge of blocking finger i194 so as to effectively preventrearward movement of the finger iii-t. Thus the lever 1% is blocked fromrocking movement from its home position to its shifted position shown inbroken lines in FIG. 1, and the linking connection between its rightwardtip 106 and clutch slide 15 will prevent any movement of the slide 15 inthe direction to release and actuate the clutch-cam assembly C.

I claim:

1. In a calculating machine, of elongated form, front to rear, incombination: memory means to register a keyboard-punched numeral fortransfer to an accumulator; clearing means to restore said memory meansto a home position for registering another numeral; a correction leveroperable on said clearing means for correctional clearing, saidcorrection lever being mounted at one side of the machine on a pivot andprojecting upwardly therefrom for forward swinging movement to effectsaid correction clearing, said lever having a forwardly projectingblocking finger; power control means disposed at the other side of themachine near its forward end, for initiating cycles of transfer fromsaid memory means to an accumulator; and an interlock lever extendingtransversely across said forward end of the machine and pivoted theretointermediate its ends for rocking movement in a substantially horizontalplane, said interlock lever having one end linked to said power controlmeans for fore-aft swinging movement, and its other end movablerearwardly in response to actuation of said power control means, to aposition extending beneath said blocking finger to prevent forwardmovement of said correction key, said blocking finger having avertically extending arcuate forward face which moves downwardly whensaid correction key is actuated, to a position blocking rearwardmovement of said other end of the interlock lever so as to preventactuation of said power control means; whereby said interlock lever iseffective to permit independent actuation of either said correctionlever or said power control means while preventing simultaneousactuation of both.

2. In a calculating machine, in combination: a frame; memory meanscomprising a carriage having a plurality of banks of memory pins movableto displaced numeral-registering positions in response to manualactuation of numeral keys on a keyboard; means mounting said carriage insaid frame for stepping movements from a home position to successivedigital positions; clearing means for restoring said carriage to itshome position; a correction lever operable on said clearing means forcorrectional clearing, said correction lever being mounted at one sideof the machine on a pivot and projecting upwardly therefrom for forwardswinging movement to effect said correction clearing, said lever havinga forwardly projecting blocking finger; power control means disposed atthe other side of the machine near its forward end, for initiatingcycles of transfer from said memory means to an accumulator; and aninterlock lever extending transversely across said forward end of themachine and pivoted thereto intermediate its ends for rocking movementin a substantially horizontal plane, said interlock lever having one endlinked to said power control means for fore-aft swinging movement, andits other end movable rearwardly in response to actuation of said powercontrol means, to a position extending beneath said blocking finger toprevent forward movement of said correction key, said blocking fingerhaving a vertically extending arcuate forward face which movesdownwardly when said correction key is actuated, to a position blockingrearward movement of said other end of the interlock lever so as toprevent actuation of said power control meansywhereby said interlocklever is effective to permit independent actuation of either saidcorrection lever or said power control means while preventingsimultaneous actuation of both.

3. A calculating machine as defined in claim 2, wherein said frameincludes a vertical fore-aft member having a fore-aft slot in which saidother end of the interlock lever is slidable and supported to resistdownward deflection by said correction lever finger.

4. A calculating machine as defined in claim 3, said frame including akeyboard plate to the underside of which said interlock lever ispivoted, said other end of the interlock lever being offset downwardlyfrom the body thereof.

5. A calculating machine as defined in claim 2, wherein said powercontrol means includes a longitudinally movable link extending alongsaid other side of the machine and having in its forward end a slotthrough which said interlock lever is extended to provide a linkingconnection to said link.

References Cited by the Examiner UNITED STATES PATENTS 1,249,554 12/17Thieme 235-6031 1,455,280 5/23 Vickers 235-6017 2,203,533 6/40Landsiedel 235- 2,733,858 2/56 Anderson 235 2,905,382 9/59 Carnacina235-60 2,942,776 6/60 Anderson 23560 2,989,231 6/61 Mark et a1 235-445LEO SMILOW, Primary Examiner.

1. IN A CALCULATING MACHINE, OF ELONGATED FORM, FRONT TO REAR, INCOMBINATION: MEMORY MEANS TO REGISTER A KEYBOARD-PUNCHNED NUMERAL FORTRANFER TO AN ACCUMULATOR; CLEARNING MEANS TO RESTORE SAID MEMORY MEANSTO A HOME POSITION FOR REGISTERING ANOTHER NUMERAL; A CORRECTION LEVEROPERABLE ON SAID CLEARING MEANS FOR CORRECTIONAL CLEARING, SAIDCORRECTION LEVER BEING MOUNTED AT ONE SIDE OF THE MACHINE ON A PIVOTPROJECTING AND PROPEJECTING UPWARDLY THERE FROM FOR FORWARD SWINGINGMOVEMENT TO EFFECT SAID CORRECTION CLEARING, SAID LEVER HAVING AFORWARDLY PROJECTING BLOCKING FINGER; POWER CONTTROL MEANS DISPOSED ATTHE OTHER SIDE OF THE MACHINE NEAR ITS FORWARD END, FOR INITIATINGCYCLES OF TRANSFER FROM SAID MEMORY MEANS TO AN ACCUMULATOR; AND ANINTERLOCK LEVER EXTENDING TRANSVERSELY ACROSS SAID FORWARD END OF THEMACHINE ANDPIVOTED THERETO INTERMEDIATE ITS ENDS FOR ROCKING MOVEMENT INA SUBSTANTIALLY HORIZONTAL PLANE, SAID INTERLOCK LEVER HAVING ONE ENDLINED TO SAID POWER CONTROL MEANS FOR FORE-AFT SWINGING MOVEMENT, ANDITS OTHER END MOVABLE REARWARDLY IN RESPONSE TO ACTUATION OF SAID POWERCONTROL MEANS, TO A POSITION EXTENDING BENEATH SAID BLOCKING FINGER TOPREVENT FORWARD MOVEMENT OF SAID CORRECTION KEY, SAID BLOCKING FINGERHAVING A VERTICALLY EXTENDING ARCUATE FORWARD FACE WHICH MOVESDOWNWARDLY WHEN SAID CORRECTION KEY IS ACTUATED, TO A POSITION BLOCKINGREARWARD MOVEMENT OF SAID OTHER END OF THE INTERLOCK LEVER SO AS TOPREVENT ACTUATION OF SAID POWER TO CONTROL MEANS; WHEREBY SAI INTERLOCKLEVER IS EFFECTIVE TO PERMIT INDEPENDENT ACTUATION OF EITHER SAIDCORRECTION LEVER OR SAID POWER CONTROL MEANS WHILE PREVENTINGSIMULTANEOUS ACTUATION OF BOTH.